Element stress or Gridpoint stress

Sid_22073
Sid_22073 Altair Community Member
edited April 2023 in Community Q&A

Dear All,

Which vonmises stresses are to be evaluated for the 2nd order tetra elements ? Elemental stress or Gridpoints streses

I see very different results of von-mises for Element and Grid point stresses

pic 1 : Elemental stresses ( 2D&3D) , vonMises

image

 

Pic 2 : Grid point stresses (Global ), vonMises

image

Could someone explain the difference and which is more close to failure vonMises criteria ?

 

Kind regards,

SId

Answers

  • Adriano_Koga
    Adriano_Koga
    Altair Employee
    edited April 2023

    they're both vonMises, but what changes is where they're calculated.

    By default, Elemental Stress is calculated at the Gauss points and interpolated to the element centroid. You can change this option, for example, requesting corner data, and then in HV plot nodal stresses by adding some averaging.

     

    GPSTRESS kind of does this for you, and already give you the stress values at the nodes, and not element centroid.

     

    If your mesh is refined enough, very little difference is expected.